function shipei(dom) {
    detectZoom();
    window.onresize = function() {
        detectZoom();
    };

    function detectZoom() {
        dom.css({
            width: "3840px",
            height: "1080px",
        });
        var ratio = window.innerWidth / window.innerHeight;
        var biaozhun = 3840 / 1080;
        var scale = 1;
        if (ratio > biaozhun) {
            scale = window.innerHeight / 1080;
            dom.css({
                transform: "scale(" + scale + ") ",
                "transform-origin": "0 0",
                width: window.innerWidth / scale,
            });
        } else {
            scale = window.innerWidth / 3840;
            dom.css({
                transform: "scale(" + scale + ") ",
                "transform-origin": "0 0",
                height: window.innerHeight / scale,
            });
        }
    }
}